o2 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



Mr. Green aud Mr. Wilrnot both procured eggs this season from the 

 Detroit River. Mr. Green made use of a newly-devised apparatus for 

 hatching, that proved to be a most excellent contrivance, both for the 

 economy of space and the facility for caring for the eggs. By this 

 method he will be enabled to hatch five or six times the quantity of eggs 

 in the same building. The young fishes were distributed in accordance 

 with the excellent i^lan adopted by the New York commissioners for 

 supplying demands from all parts of the State, without expense, on ap- 

 jilication. 



The success attained by these persevering experiments is now com- 

 plete, and the white-fish may be restored by artificial ijropagation, to 

 the same extent as the salmon, or the brook-trout, or the shad. As has 

 been shown, the white-fish has advantages in this particular that the 

 other S])ecies have not. The obstruction of streams is no obstacle in the 

 way of their multiplication, because they have no necessity of ascend- 

 ing them, and, unlike the trout aud the salmon, they cannot be suspected 

 of eating each other. 



Attempts at feeding the young fishes have all been failures,, and the 

 only natural food that has been found in their intestines is the species 

 of Dlatomaeew reported by Mr. Briggs. But as they are more vigor- 

 ous and strong in the earlier stages of growth, there is not the same ne- 

 cessity of caring for them until they are partly grown, and they should 

 be put into the waters they are to inhabit soon after the ovisac is ab- 

 sorbed, and allowed to find their natural food for themselves, just as the 

 young shad are treated when hatched artificially. 



Artificial propagation alibrds advantages that compensate for all the 

 overfishing and losses that the fish-fauna^ suffer from man and natural 

 causes. The great numbers of eggs found in the ovaries of fishes in 

 reality afford little evidence of their capacity for populating the waters. 



It is a fact, illustrated in nearly if not all branches of the animal 

 kingdom, that the most fecund species do not, by any means, increase 

 the fastest in numbers, but from the greater evils they are subject to, 

 and the greater number of enemies they encounter, there is such a 

 fatality during the earlier stages of growth that the losses balance the 

 numbers produced, and less fecund species, by being* better protected, 

 equal them in niunbers. 



The most perfect illustrations of this fact may be found among our 

 lake-fishes. The muskellunge, JEsox iiohilior, has a very large number of 

 eggs. A cast of the ovaries of a large female specimen, made by Dr. E. 

 Sterling, of Cleveland, Ohio, is in the possession of the Smithsonian 

 Institution. The ovaries measure over two feet in length, and the eggs 

 are about the same diameter as those of the w^hite-tish ; they contain 

 at least five times as many eggs as a pound white-fish, and yet, as 

 regards numbers, the muskellunge is a comparatively rare fish. There 

 are, undoubtedly, exigencies attending the egg-stage of this fish that 

 will account for this fact. 



In the case of the white-fishes, though annually depositing millions 



